4. The shares of Common Stock are directly beneficially owned by BVF Investments, LLC ("BVFLLC"), a Delaware limited liability company. Pursuant to the operating agreement of BVFLLC, BVF Partners, L.P., a Delaware limited partnership ("Partners") is authorized, among other things, to invest the contributed capital of Samana Capital, L.P., the majority member of BVFLLC, in the shares of Common Stock and other securities and to vote, exercise or convert and dispose of such securities and is entitled to receive fees based on assets under management and, subject to certain exceptions, allocations based on realized and unrealized gains on such assets.

5. The shares of Common Stock are indirectly beneficially owned by Partners. Partners is the general partner of BVF and BVF II, the manager of BVFLLC and the general partner, manager and investment advisor, as the case may be, of the members of BVF X LLC.

6. The shares of Common Stock are indirectly beneficially owned by BVF Inc., a Delaware corporation ("BVF Inc."). BVF Inc. is the general partner of Partners.

7. Mark N. Lampert is the sole shareholder, sole director, and an officer of BVF Inc.